一种基于坐标转换的危岩立面正射影像获取方法

针对危岩类地形地貌,该文提出一种基于坐标转换的危岩立面正射影像获取方法。首先以旋翼式无人机采集的危岩立面影像序列为基础数据,采用实景建模软件Context Capture,生成危岩立面三维模型;然后在危岩立面三维模型上选取若干离散点和易于识别的像控点,通过离散点拟合得到危岩立面的拟合竖直平面,并对其进行坐标转换,使其平行于水平面,同时得到危岩立面像控点坐标转换后的新坐标;最后在Context Capture中输入危岩立面像控点新坐标,重新三维建模,得到坐标转换后的危岩立面三维模型,并输出危岩立面正射影像。通过实验,验证和分析了该方法的有效性。

A Method of Getting Orthophoto of Dangerous Rock Facades Based on Coordinate Conversion

According to the geomorphology of dangerous rocks, this paper introduces a method for getting orthophoto of dangerous rock facades based coordinate conversion. Firstly, based on the image sequence of dangerous rock facade collected by Rotor UAV, the threedimensional model of dangerous rock facade is generated by using the scene modeling software ContextCapture;Then several discrete points and easily identifiable image control points are selected on the threedimensional model of dangerous rock facade, and the fitting vertical plane of dangerous rock facade is obtained by fitting discrete points, and the coordinate transformation is carried out to make it parallel to the level. At the same time, the new coordinates of image control points of dangerous rock facades are obtained after coordinate transformation. Finally, the new coordinates of image control points of dangerous rock facades are input in ContextCapture, and the three-dimensional model is reconstructed. The three-dimensional model of dangerous rock facades after coordinate transformation is obtained , and the orthophoto of dangerous rock facades is output. Through the experiments, the validity of this method is verified and analysed.